variations -- the number of sign changes of an ordered list of numbers

• Usage:

  variations(l)

• Inputs:
  • l, a list, of numbers
• Outputs:
  • an integer, the number of sign changes in the ordered list l

i1 : L = for i to 10 list random(-50,50)

o1 = {-26, 15, 21, 22, -31, -31, 41, 22, 43, 29, 22}

o1 : List

i2 : variations(L)

o2 = 3